Electrical contact mounting



Oct. 26,1926. 1,604,154

J. E. ERSKINE ELIECTRI CAL CONTACT MOUNTING Filed March 12. 1921 JamesE. Emkine. WIT/ E8858 INVENTOR I Arron/45m Patented Oct. 26, 1926.

UNITED STATES JAMES EDISON ERSKINE, F JACKSONVILLE, FLORIDA, ASSIGNOR T0GEORGE W.

1,604,154 PATENT, OFFICE.

TROUT, OF DUVAL COUNTY, FLORIDA.

ELECTRICAL CONTACT MOUNTING.

Application filed March 12, 1921. Serial No. 451,691.

My invention relates to improvements in mountings for electricalcontacts, and it consists in the constructions, combinations and mode ofoperation herein described and cl aimed.

One of the foremost objects of the inven tion is to provide a mountingof such ar rangement that the contact may seat itself perfectly.

A further object of the invention is to provide a universally movablemounting for electric contacts, through the functioning of whichadjacent plane contact surfaces may establish complete engagement.

A further object of the invention is to provide a mounting of thecharacter described, comprising a universally movable foundation of basemetal, to a plane surface of which a small disk of platinum or otherhigh resistance material is aflixed.

Other objects and advantages will appear in the following specification,reference being had to the accompanying drawing, in which Figure 1 is aside elevation of an induction coil showing the improved mounting inplace on the contact arm,

Figure 2 is a plan view,

Figure 3 is a longitudinal section taken substantially on the line 3-3of Figure 2,

Figure 4.- is a view partly in elevation and partly in section,illustrating a modification wherein the universal mounting is carried bythe vibrator instead of by the contact arm,

Figure 5 is a section similar to Figure 3, illustrating the modifiedform of spring for holding the universal mounting in place,

Figure 6 is a section on the line 66 of Figure 7 illustrating anothermodification, and

Figure 7 is an elevation showing how the mounting in Figure 6 appearswhen viewed in the plane of the line 77.

As indicated in the objects of the invention stated above, the purposeof the improved mounting is to insure cooperating contacts seatingperfectly against each other so as to provide a complete path for thepassage of the electric current, and therefore in a large measureeliminating sparking, which comes from imperfectly seated contacts, andpitting of the contact surfaces, which also comes from the same cause.Four arrangements for securing the ultimate result are illustrated inthe drawing and each of these is described in detail below. Take firstthe preferred form in Figure 8. The coil C, well shown in Figures 1 and2, is of a con vent-ional type. In so far as the invention is concerned,the coil includes the contact arm 1 and the. vibrator 2. The former isfixed at 3, but the free end is adjustable by means of the screw 4:which operates in the downward direction against the tension of thespring 5. The vibrator 2 is also fixed, but its free end vibratesbetween the exposed core end 6 and the contact of the improved mountingon the contact arm 1.

Instead of being perfectly straight, as is now the case, the contact arm1 is embossed directly over the core 6 to provide semi spherical socket7 in which the foundation 8 of base metal or other material, has limitedoscillatory motion. It is retained by the stud 9 which passes throughthe hole 10 in the bottom of the socket 7 the head of the stud beingheldup by the spring mounting 11. This spring mounting may be made in theshape of a cross as suggested in Figure 2, or it may be made in othershapes. Its purpose is to seat the foundation 8 in the socket 7 withsufiicient firmness to prevent any lost motion, but at' the same timeyielding sufficiently to permit the limited turn ing motion to which thefoundation is susceptible.

A contact 12 of more precious metal, as for instance, platinum or othersuitable high resistance material, is attached at 13 in the bottom planeface of the foundation 8. This contact cooperates with a similar contact14: on the vibrator 2. After the contacts have once been alined, thereis no further movement until the contacts are disturbed, then there willbe a tendency toward a slight turning motion of the foundation 8 in itssocket 7, insuring the perfect engagement of the companion plane facesof the contacts so that there may be a imiform current path for theelimination of sparking.

The modification in Figure 4, shows the foundation 8 as being seated ina socket 7 in the vibrator 2 instead of in a similar socket in thecont-act arm above. The contact 14: is now carried by the contact arm1,-and the contact 12 is keyed in the foundation 8 at 13 the same asbefore.

The stud 9 passes through a hole in the vibrator 2, and a spring 11*,similar to the and it cooperates with a contact 14 on the vibrator 2.

But instead of being held in place bya' leaf spring in the shape of across, as in Figure 2, the foundation 8 is supported by the spiralspring 15", and for the purpose of providing an adequate abutment on thestud against which the upper end of the spring shall rest, the head ofthestud is made con- .siderably larger than in Figure 3, and the studitself is? also considerably longer. It should .be remembered that thesections in Figures 3, 4t, 5, and 6 are larger than-actual size, so thevarious dimensions shown in these views must be considered as much morewhen reduced to the actual working sizes.

The modification in Figure 6 comprises a gimbal ring 16, mounted in anopening 1'? in the contact armrli- The ring 16 has prongs 18 atdiametrically opposite points, which enable lateral rocking motion.

The foundation 8 in this instance flat instead of spherical as in Figure3, has prongs 19 at diametrically opposite points, but these are mountedin recesses inside of the gimbal ring 16 at places ninety degrees aroundfrom the prongs 18. The contact 12? is keyed in place at 13 and thiscontact is as capable'of adjusting itself in respect tothe contact 14 ofthe vibrator 2, as are any of the contacts in the Vt'oregoingmodification.

The reader can now readily understand that inany of the various formsofthe invention there is provided a universal mounting for a contact withwhich another movable contact cooperates, that [universal mountingenabling a perfect engagement of as herein described and claimed, isthat of I a generally preferred form, obviously other modifications andchanges may be made without departing from the spirit otthe invention orthe scope of the claims.

I claim:v V

1. An electrical contact mounting, con: prising an arm with an embossedrecess pro- ,vided with an opening,a foundation seated in the recess,with a headed stud passing through the opening; a conta'ctkeyed to thefoundation, and resilient means between the stud head and arm, retainingthe foundation but permitting limited oscillatory motion.

2. an electrical contact mounting, comprising a bar wlth an embossedrecess having a central hole, a foundationof base material swivtlled inthe recess byahead'ed stud passing through the hole, and having a;contact disk of rare metal keyed on a face; and a spring betweenthe'stud head andbar retaining the foundation.

3. An electrical contact mounting comprising a, contact having a portionotspherical form, an element extending from the spherical portion of thecontact, an enlargement on said element, a support having a concavity toreceive said spherical portion and an opening larger than said elementto enable the latter to pass through, and resilient means seated betweenthe support and said enlar ement tokeep the spherical portion inengagementwith the concavity, said enlarged opening enabling oscillatingmove ment of the element when the contact moves in the concavity.

